This invention relates to the field of industrial cleaning, and particularly to a method and means for cleaning containers used in the food industry. In such applications it is very important that all traces of residual matter, including biological organisms, be removed from a container intended for reuse. As is well known, ordinary immersion washing procedures are imperfect in this respect, particularly where the containers to be cleaned have corners, edges, or joints where undesired matter tends to collect.
The particular containers which this invention is especially designed to clean are called "fish boxes". They are used to receive tuna fish off the ship, for freezing and transportation from shipside to cold storage at the entrance to the tuna packing plant. The boxes are rectangular and quite large: since they are of metal they weigh several hundred pounds.
When needed for processing, the fish are thawed with warm water and removed from the boxes, which then contain residues of fish oil, fish skin, sea water, and the foam that develops as the fish begin to thaw. It is necessary to clean and sterilize the boxes for reuse. Washing procedures involving submersion in cleaning liquid are not practical with such large objects, and also tend to perform imperfect cleaning along the edges and corners of the boxes.